U.S. patent application number 11/227600 was filed with the patent office on 2007-10-11 for methods and apparatus for cooling gas turbine engine components.
This patent application is currently assigned to General Electric Company. Invention is credited to David Martin Johnson, Gilbert Otto Kraemer, James Anthony West.
Application Number | 20070234729 11/227600 |
Document ID | / |
Family ID | 38573652 |
Filed Date | 2007-10-11 |
United States Patent
Application |
20070234729 |
Kind Code |
A1 |
West; James Anthony ; et
al. |
October 11, 2007 |
Methods and apparatus for cooling gas turbine engine components
Abstract
A method for cooling a turbine assembly component of a gas
turbine engine in a combined-cycle power generation system. The
method includes channeling cooling fluid that is extracted from a
source external to the gas turbine engine to the turbine assembly
component, and cooling the turbine assembly component using the
cooling fluid.
Inventors: |
West; James Anthony;
(Simpsonville, SC) ; Kraemer; Gilbert Otto;
(Greer, SC) ; Johnson; David Martin;
(Simpsonville, SC) |
Correspondence
Address: |
JOHN S. BEULICK (17851)
ARMSTRONG TEASDALE LLP
ONE METROPOLITAN SQUARE, SUITE 2600
ST. LOUIS
MO
63102-2740
US
|
Assignee: |
General Electric Company
|
Family ID: |
38573652 |
Appl. No.: |
11/227600 |
Filed: |
September 15, 2005 |
Current U.S.
Class: |
60/772 ;
60/806 |
Current CPC
Class: |
F05D 2260/232 20130101;
F01D 25/12 20130101; F02C 7/185 20130101 |
Class at
Publication: |
060/772 ;
060/806 |
International
Class: |
F02C 7/12 20060101
F02C007/12 |
Claims
1. A method for cooling a turbine assembly component of a gas
turbine engine in a combined-cycle power generation system, said
method comprising: channeling cooling fluid that is extracted from
a source external to the gas turbine engine to the turbine assembly
component; and cooling the turbine assembly component using the
cooling fluid.
2. A method in accordance with claim 1 wherein the combined-cycle
system includes an air separation unit, said method further
comprises separating nitrogen process gas and oxygen from air using
the air separation unit, and channeling a cooling fluid comprises
channeling nitrogen process gas from the air separation unit to the
turbine assembly component.
3. A method in accordance with claim 1 wherein the combined-cycle
system includes a clean-up device and channeling a cooling fluid
comprises channeling carbon dioxide from the clean-up device to the
turbine assembly component.
4. A method in accordance with claim 1 wherein channeling a cooling
fluid comprises channeling the cooling fluid to a turbine nozzle
assembly of the turbine assembly.
5. A method in accordance with claim 1 wherein channeling a cooling
fluid comprises channeling the cooling fluid through a pipe that is
coupled in flow communication to the gas turbine engine adjacent a
compressor of the gas turbine engine and that is coupled in flow
communication to the gas turbine engine adjacent the turbine
assembly.
6. A combined-cycle power generation system comprising: a gas
turbine engine comprising a turbine assembly; an air separation
unit configured to separate oxygen and nitrogen process gas from
air to thereby generate a flow of nitrogen process gas and a flow
of oxygen, said air separation unit comprising a nitrogen outlet
that exhausts nitrogen process gas from said air separation unit;
and a conduit coupled in flow communication to said nitrogen outlet
and coupled in flow communication to said turbine assembly, said
conduit configured to channel nitrogen process gas discharged from
said nitrogen outlet to said turbine assembly to facilitate cooling
a component within said turbine assembly.
7. A system in accordance with claim 6 wherein said turbine
assembly component comprises a turbine nozzle assembly.
8. A system in accordance with claim 6 further comprising a pipe
coupled in flow communication to said gas turbine engine adjacent a
compressor of said gas turbine engine, said pipe configured to
channel extraction air from said compressor to said turbine
assembly component, said conduit coupled in flow communication to
said pipe between said gas turbine engine compressor and said
turbine assembly component.
9. A system in accordance with claim 6 further comprising a
gasifier configured to generate fuel for use by said gas turbine
engine, said gasifier coupled in flow communication to said gas
turbine engine.
10. A system in accordance with claim 6 further comprising: a steam
turbine; and a heat recovery steam generator coupled to said gas
turbine engine and said steam turbine, said heat recovery steam
generator configured to generate steam using exhaust gas received
from said gas turbine engine, said heat recovery steam generator
further configured to discharge steam to said steam turbine.
11. A system in accordance with claim 6 wherein said air separation
unit is configured to generate a flow of nitrogen process gas
comprising between about 95% and 100% nitrogen.
12. A combined-cycle power generation system comprising: a gas
turbine engine comprising a turbine assembly; a gasifier configured
to generate fuel for use by said gas turbine engine; a clean-up
device configured to separate carbon dioxide from the fuel
generated by said gasifier, said clean-up device comprising a
carbon dioxide outlet that exhausts a flow of carbon dioxide from
said clean-up device; and a conduit coupled in flow communication
to said carbon dioxide outlet and coupled in flow communication to
said turbine assembly, said conduit configured to channel carbon
dioxide discharged from said carbon dioxide outlet to said turbine
assembly to facilitate cooling a component within said turbine
assembly.
13. A system in accordance with claim 12 wherein said turbine
assembly component comprises a turbine nozzle assembly.
14. A system in accordance with claim 12 further comprising a pipe
coupled in flow communication to said gas turbine engine adjacent a
compressor of said gas turbine engine, said pipe configured to
channel extraction air from said compressor to said turbine
assembly component, said conduit coupled in flow communication to
said pipe between said gas turbine engine compressor and said gas
turbine engine component.
15. A system in accordance with claim 12 further comprising an air
separation unit configured to separate oxygen and nitrogen process
gas from air to thereby generate a flow of nitrogen process gas and
a flow of oxygen, said air separation unit coupled in flow
communication to said gasifier.
16. A system in accordance with claim 12 further comprising: a
steam turbine; and a heat recovery steam generator coupled to said
gas turbine engine and said steam turbine, said heat recovery steam
generator configured to generate steam using exhaust gas received
from said gas turbine engine, said heat recovery steam generator
further configured to discharge steam to said steam turbine.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to integrated gasification
combined-cycle (IGCC) power generation systems, and more
specifically to methods and apparatus for cooling gas turbine
engine components in IGCC systems.
[0002] At least some known IGCC systems include a gasification
system that is integrated with at least one power producing turbine
system. For example, known gasifiers convert a mixture of fuel, air
or oxygen, steam, and/or limestone into an output of partially
combusted gas, sometimes referred to as "syngas". The hot
combustion gases are supplied to the combustor of a gas turbine
engine, which powers a generator that supplies electrical power to
a power grid. Exhaust from at least some known gas turbine engines
is supplied to a heat recovery steam generator that generates steam
for driving a steam turbine. Power generated by the steam turbine
also drives an electrical generator that provides electrical power
to the power grid.
[0003] At least some known gasification processes may generate
flows of nitrogen. For example, an air separation unit used to
generate and supply oxygen to the gasifier may generate oxygen by
separating nitrogen and oxygen from a supply of air. Some of the
nitrogen may be used to facilitate controlling emissions generated
by the gas turbine engine. For example, nitrogen may be injected
into the combustion zone of the gas turbine engine to reduce
combustion temperatures, and to reduce nitrous oxide emissions from
the gas turbine engine. However, even if some nitrogen is used for
emissions control, some excess nitrogen may still be generated.
Excess nitrogen is typically vented from known IGCC systems to the
atmosphere.
BRIEF DESCRIPTION OF THE INVENTION
[0004] In one aspect, a method is provided for cooling a turbine
assembly component of a gas turbine engine in a combined-cycle
power generation system. The method includes channeling cooling
fluid that is extracted from a source external to the gas turbine
engine to the turbine assembly component, and cooling the turbine
assembly component using the cooling fluid.
[0005] In another aspect, a combined-cycle power generation system
includes a gas turbine engine including a turbine assembly, and an
air separation unit configured to separate oxygen and nitrogen
process gas from air to thereby generate a flow of nitrogen process
gas and a flow of oxygen. The air separation unit includes a
nitrogen outlet that exhausts nitrogen process gas from the air
separation unit. The system also includes a conduit coupled in flow
communication to the nitrogen outlet and coupled in flow
communication to the turbine assembly. The conduit is configured to
channel nitrogen process gas discharged from the nitrogen outlet to
the turbine assembly to facilitate cooling a component within the
turbine assembly.
[0006] In another aspect, a combined-cycle power generation system
includes a gas turbine engine comprising a turbine assembly, a
gasifier configured to generate fuel for use by the gas turbine
engine, and a clean-up device configured to separate carbon dioxide
from the fuel generated by the gasifier. The clean-up device
includes a carbon dioxide outlet that exhausts a flow of carbon
dioxide from the clean-up device. The system also includes a
conduit coupled in flow communication to the carbon dioxide outlet
and coupled in flow communication to the turbine assembly. The
conduit is configured to channel carbon dioxide discharged from the
carbon dioxide outlet to the turbine assembly to facilitate cooling
a component within the turbine assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a schematic illustration of an exemplary gas
turbine engine.
[0008] FIG. 2 is a perspective view of an exemplary turbine nozzle
assembly for use in a gas turbine engine, such as the exemplary gas
turbine engine shown in FIG. 1.
[0009] FIG. 3 is a schematic diagram of an exemplary known
integrated gasification combined-cycle (IGCC) power generation
system.
[0010] FIG. 4 is a schematic diagram of an exemplary embodiment of
an IGCC power generation system of the present invention.
[0011] FIG. 5 is a schematic diagram of an alternative embodiment
of the IGCC system shown in FIG. 4.
[0012] FIG. 6 is a schematic diagram of a further alternative
embodiment of the IGCC system of the present invention.
[0013] FIG. 7 is a schematic diagram of an alternative embodiment
of the IGCC system shown in FIG. 6.
DETAILED DESCRIPTION OF THE INVENTION
[0014] FIG. 1 is a schematic illustration of an exemplary gas
turbine engine 10 including at least one compressor 12, a combustor
14, and a turbine 16 connected serially. Compressor 12 and turbine
16 are coupled by a shaft 18, which also couples turbine 16 and a
driven load 20. In one embodiment, engine 10 is an 7FB engine
commercially available from General Electric Company, Greenville,
S.C. Engine 10 illustrated and described herein is exemplary only.
Accordingly, engine 10 is not limited to the gas turbine engine
shown in FIG. 1 and described herein, but rather, engine 10 may be
any gas turbine engine. For example, in an alternative embodiment,
engine 10 is a multi-shaft gas turbine engine having two turbines
(not shown) for separately driving driven load 20 and compressor
12.
[0015] In operation, air flows into engine 10 through compressor 12
and is compressed. Compressed air is then channeled to combustor 14
where it is mixed with fuel and ignited. Airflow from combustor 14
drives rotating turbine 16 and exits gas turbine engine 10 through
an exhaust nozzle 22. Additionally, in some embodiments exhaust
gases from engine 10 may be supplied to a heat recovery steam
generator (not shown in FIG. 1) that generates steam for driving a
steam turbine (not shown in FIG. 1).
[0016] FIG. 2 is a perspective view of an exemplary turbine nozzle
assembly 30 that may be used with a gas turbine engine, such as
engine 10 (shown in FIG. 1). In the exemplary embodiment, nozzle
assembly 30 includes two airfoils 32 and is generally known as a
doublet. In such an embodiment, a plurality of turbine nozzle
assemblies 30 are circumferentially coupled together to form a
turbine nozzle ring. In the exemplary embodiment, doublet 30
includes a plurality of circumferentially-spaced airfoils 32
coupled together by an arcuate radially outer band or platform 34,
and an arcuate radially inner band or platform 36. More
specifically, in the exemplary embodiment, each band 34 and 36 is
integrally-formed with airfoil 32, and each doublet 30 includes two
airfoils 32. Turbine nozzle assembly 30 illustrated and described
herein is exemplary only. Accordingly, turbine nozzle assembly 30
is not limited to the assembly shown in FIG. 2 and described
herein, but rather, assembly 30 may be any turbine nozzle assembly.
For example, in an alternative embodiment, turbine nozzle assembly
30 includes a single airfoil 32 and is generally known as a
singlet. In yet another alternative embodiment, and for example,
turbine nozzle assembly 30 includes three airfoils 32 and is
generally known as a triplet.
[0017] FIG. 3 is a schematic diagram of an exemplary known
integrated gasification combined-cycle (IGCC) power generation
system 50. IGCC system 50 generally includes a main air compressor
52, an air separation unit 54 coupled in flow communication to
compressor 52, a gasifier 56 coupled in flow communication to air
separation unit 54, a gas turbine engine, such as gas turbine
engine 10, coupled in flow communication to gasifier 56, and a
steam turbine 58. In operation, compressor 52 compresses ambient
air. The compressed air is channeled to air separation unit 54. In
some embodiments, in addition or alternative to compressor 52,
compressed air from gas turbine engine compressor 12 is supplied to
air separation unit 54. Air separation unit 54 uses the compressed
air to generate oxygen for use by gasifier 56. More specifically,
air separation unit 54 separates the compressed air into separate
flows of oxygen and a gas by-product, sometimes referred to as a
"process gas". The process gas generated by air separation unit 54
includes nitrogen and will be referred to herein as "nitrogen
process gas". The nitrogen process gas may also include other gases
such as, but not limited to, oxygen and/or argon. For example, in
some embodiments, the nitrogen process gas includes between about
95% and about 100% nitrogen. The oxygen flow is channeled to
gasifier 56 for use in generating partially combusted gases,
referred to herein as "syngas" for use by gas turbine engine 10 as
fuel, as described below in more detail. In some known IGCC systems
50, at least some of the nitrogen process gas flow, a by-product of
air separation unit 54, is vented to the atmosphere. Moreover, in
some known IGCC systems 50, some of the nitrogen process gas flow
is injected into a combustion zone (not shown) within gas turbine
engine combustor 14 to facilitate controlling emissions of engine
10, and more specifically to facilitate reducing the combustion
temperature and reducing nitrous oxide emissions from engine 10.
IGCC system 50 may include a compressor 60 for compressing the
nitrogen process gas flow before being injected into the combustion
zone.
[0018] Gasifier 56 converts a mixture of fuel, the oxygen supplied
by air separation unit 54, steam, and/or limestone into an output
of syngas for use by gas turbine engine 10 as fuel. Although
gasifier 56 may use any fuel, in some known IGCC systems 50,
gasifier 56 uses coal, petroleum coke, residual oil, oil emulsions,
tarsands, and/or other similar fuels. In some known IGCC systems
50, the syngas generated by gasifier 56 includes carbon dioxide.
The syngas generated by gasifier 52 may be cleaned in a clean-up
device 62 before being channeled to gas turbine engine combustor 14
for combustion thereof. Carbon dioxide may be separated from the
syngas during clean-up and, in some known IGCC systems 50, vented
to the atmosphere. The power output from gas turbine engine 10
drives a generator 64 that supplies electrical power to a power
grid (not shown). Exhaust gas from gas turbine engine 10 is
supplied to a heat recovery steam generator 66 that generates steam
for driving steam turbine 58. Power generated by steam turbine 58
drives an electrical generator 68 that provides electrical power to
the power grid. In some known IGCC systems 50, steam from heat
recovery steam generator 62 is supplied to gasifier 52 for
generating the syngas.
[0019] FIG. 4 is a schematic diagram of an exemplary embodiment of
an integrated gasification combined-cycle (IGCC) power generation
system 70 of the present invention. As described above, air
separation unit 54 generates a flow of nitrogen process gas as a
by-product of generating a flow of oxygen for gasifier 56. In some
known IGCC systems, such as IGCC system 50 (shown in FIG. 3), at
least some of the nitrogen process gas flow is vented to the
atmosphere, which may be wasteful. For example, the nitrogen
process gas vented to the atmosphere may represent a loss of energy
from the IGCC system that could otherwise be utilized. Accordingly,
IGCC system 70 uses at least some of the nitrogen process gas flow
generated by air separation unit 54 to facilitate cooling a turbine
nozzle assembly component of gas turbine engine 10, such as, in the
exemplary embodiment, turbine nozzle assembly 30 (shown in FIG. 2).
In other embodiments, and for example, at least some of the
nitrogen process gas flow generated by air separation unit 54 may
be used to facilitate cooling turbine assembly buckets (not shown)
and/or may be used to facilitate purging turbine assembly
wheelspaces (not shown). IGCC system 70 thereby facilitates cooling
turbine nozzle assembly 30 using a cooling fluid (nitrogen process
gas) extracted from a source external to gas turbine engine 10.
More specifically, IGCC system 70 includes a conduit 72 having an
end 74 that is coupled in flow communication to a nitrogen outlet
76 of air separation unit 54 that exhausts at least some of the
nitrogen process gas flow from air separation unit 54. Another end
78 of conduit 72 is coupled in flow communication to gas turbine
engine 10 adjacent turbine nozzle assembly 30. More specifically,
conduit end 78 fluidly communicates with a cavity (not shown)
within engine 10 containing turbine nozzle assembly 30.
Accordingly, conduit 72 receives nitrogen process gas flow exhaust
from air separation unit 54 through nitrogen outlet 76, and
channels the nitrogen process gas flow into the gas turbine engine
cavity for directing nitrogen process gas toward turbine nozzle
assembly 30 to facilitate cooling assembly 30. In some embodiments,
a compressor 80 is operatively connected to conduit 72 for
compressing the nitrogen process gas flow before it is supplied to
gas turbine engine 10. Moreover, in some embodiments, conduit 72
receives all of the nitrogen process gas generated by air
separation unit 54 such that conduit 72 channels all of the
nitrogen process gas generated by air separation unit 54 to turbine
nozzle assembly 30. In other embodiments, some of the nitrogen
process gas generated by air separation unit 54 is channeled to
combustor 14 for controlling emissions of engine 10 and/or is
vented to the atmosphere.
[0020] By using the nitrogen process gas flow that may otherwise be
wasted by being vented to the atmosphere, IGCC system 70 may
facilitate reducing parasitic energy losses experienced by system
70. Moreover, because the nitrogen process gas flow exits air
separation unit 54 at about ambient temperature and at least a
substantial portion of conduit 72 is external to gas turbine engine
10, a temperature of the nitrogen process gas flow can be
heated/controlled to any desired temperature and may thereby
facilitate allowing a reduction of the flow rate of the cooling
flow that may be required to cool turbine nozzle assembly 30. In
some known IGCC systems and/or gas turbine engines, turbine nozzle
assembly 30 is cooled using compressed air extracted from a
compressor stage of engine 10. IGCC system 70 may cool turbine
nozzle assembly 30 using nitrogen process gas from air separation
unit 54 in addition or alternative to cooling via compressor
extraction air. Accordingly, in some embodiments, conduit 72 may
facilitate increasing an overall amount of cooling of turbine
nozzle assembly 30 if both nitrogen process gas from air separation
unit 54 and compressor extraction air are used to cool turbine
nozzle assembly 30. Moreover, in some embodiments, conduit 72 may
facilitate decreasing, or eliminating entirely, an amount of
compressor extraction air used to cool turbine nozzle assembly 30,
which may facilitate increasing an amount of oxygen supplied gas
turbine engine combustor 14 from gas turbine engine compressor
14.
[0021] FIG. 5 is a schematic diagram of an exemplary embodiment of
an IGCC power generation system 90 that is an alternative
embodiment of IGCC system 70 (shown in FIG. 4). As described above,
in some known IGCC systems and/or gas turbine engines, turbine
nozzle assembly 30 is cooled using compressed air extracted from a
compressor stage of engine 10. Specifically, in some known IGCC
systems and/or gas turbine engines, a pipe 92 is coupled in flow
communication to gas turbine engine 10 adjacent gas turbine engine
compressor 12 and adjacent turbine nozzle assembly 30 (shown in
FIG. 2). More specifically, an end 94 of pipe 92 is coupled in flow
communication to a cavity (not shown) of gas turbine engine 10
containing engine compressor 12 and an opposing end 96 of pipe 92
is coupled in flow communication to a cavity (not shown) of engine
10 containing turbine nozzle assembly 30. Pipe 92 channels
compressed air extracted from a compressor stage of engine
compressor 12 to turbine nozzle assembly 30 for cooling
thereof.
[0022] In the exemplary embodiment of IGCC system 90, a conduit 98
is coupled in flow communication to nitrogen outlet 76 of air
separation unit 54 that exhausts at least some of the nitrogen
process gas flow from air separation unit 54. Conduit 98 is also
coupled in flow communication to pipe 92. Accordingly, conduit 98
receives nitrogen process gas flow exhaust from air separation unit
54 through nitrogen outlet 76, and channels the nitrogen process
gas flow into pipe 92, which channels the nitrogen process gas flow
into the gas turbine engine cavity containing assembly 30 for
directing nitrogen process gas toward turbine nozzle assembly 30 to
facilitate cooling assembly 30. In some embodiments, a compressor
100 is operatively connected to conduit 98 for compressing the
nitrogen process gas flow before it is supplied to gas turbine
engine 10. Moreover, in some embodiments, a valve 102 is
operatively connected at the fluid interconnection between pipe 92
and conduit 98 for selectively controlling an amount of the
nitrogen process gas flow released into pipe 92. In some
embodiments, conduit 98 receives all of the nitrogen process gas
generated by air separation unit 54 such that conduit 98 channels
all of the nitrogen process gas generated by air separation unit 54
to turbine nozzle assembly 30. In other embodiments, some of the
nitrogen process gas generated by air separation unit 54 is
channeled to combustor 14 for controlling emissions of engine 10
and/or is vented to the atmosphere.
[0023] By using the nitrogen process gas flow that may otherwise be
wasted by being vented to the atmosphere, IGCC system 90 may
facilitate reducing parasitic energy losses experienced by system
90. Moreover, because the nitrogen process gas flow exits air
separation unit 54 at about ambient temperature and at least a
substantial portion of conduit 98 is external to gas turbine engine
10, a temperature of the nitrogen process gas flow can be
heated/controlled to any desired temperature and may thereby
facilitate allowing a reduction of the flow rate of the cooling
flow that may be required to cool turbine nozzle assembly 30. IGCC
system 90 may cool turbine nozzle assembly 30 using nitrogen
process gas from air separation unit 54 in addition or alternative
to cooling via compressor extraction air. Accordingly, in some
embodiments, conduit 98 may facilitate increasing an overall amount
of cooling of turbine nozzle assembly 30 if both nitrogen process
gas from air separation unit 54 and compressor extraction air are
used to cool turbine nozzle assembly 30. Moreover, in some
embodiments, conduit 98 may facilitate decreasing, or eliminating
entirely (despite using pipe 92 to ultimately supply nitrogen
process gas to assembly 30), an amount of compressor extraction air
used to cool turbine nozzle assembly 30, which may facilitate
increasing an amount of oxygen supplied gas turbine engine
combustor 14 from gas turbine engine compressor 14.
[0024] FIG. 6 is a schematic diagram of a further alternative
embodiment of an integrated gasification combined-cycle (IGCC)
power generation system 110 of the present invention. As described
above, clean-up device 62 produces an exhaust of carbon dioxide. In
some known IGCC systems, such as IGCC system 50 (shown in FIG. 3),
at least some of the carbon dioxide flow is vented to the
atmosphere, which may be wasteful. For example, the carbon dioxide
vented to the atmosphere may represent a loss of energy from the
IGCC system that could otherwise be utilized. Accordingly, IGCC
system 110 uses at least some of the carbon dioxide flow generated
by clean-up device 62 to facilitate cooling a turbine assembly
component of gas turbine engine 10, such as, in the exemplary
embodiment, turbine nozzle assembly 30 (shown in FIG. 2). In other
embodiments, and for example, at least some of the carbon dioxide
flow generated by clean-up device 62 may be used to facilitate
cooling turbine assembly buckets (not shown) and/or may be used to
facilitate purging turbine assembly wheelspaces (not shown). IGCC
system 110 thereby facilitates cooling turbine nozzle assembly 30
using a cooling fluid (carbon dioxide) extracted from a source
external to gas turbine engine 10. More specifically, IGCC system
110 includes a conduit 112 having an end 114 that is coupled in
flow communication to a carbon dioxide outlet 116 of clean-up
device 62 that exhausts at least some of the carbon dioxide flow
from clean-up device 62. Another end 118 of conduit 102 is coupled
in flow communication to gas turbine engine 10 adjacent turbine
nozzle assembly 30. More specifically, conduit end 118 fluidly
communicates with a cavity (not shown) within engine 10 containing
turbine nozzle assembly 30. Accordingly, conduit 112 receives
carbon dioxide flow exhaust from clean-up device 62 through carbon
dioxide outlet 116, and channels the carbon dioxide flow into the
gas turbine engine cavity for directing carbon dioxide toward
turbine nozzle assembly 30 to facilitate cooling assembly 30. In
some embodiments, a compressor 120 is operatively connected to
conduit 112 for compressing the carbon dioxide flow before it is
supplied to gas turbine engine 10. Moreover, in some embodiments,
conduit 112 receives all of the carbon dioxide generated by
clean-up device 62 such that conduit 112 channels all of the
nitrogen generated by clean-up device 62 to turbine nozzle assembly
30. In other embodiments, some of the carbon dioxide generated by
clean-up device 62 is vented to the atmosphere.
[0025] By using the carbon dioxide flow that may otherwise be
wasted by being vented to the atmosphere, IGCC system 110 may
facilitate reducing parasitic energy losses experienced by system
110. Moreover, because the carbon dioxide flow exits clean-up
device 62 at about ambient temperature and at least a substantial
portion of conduit 112 is external to gas turbine engine 10, a
temperature of the carbon dioxide flow can be heated/controlled to
any desired temperature and may thereby facilitate allowing a
reduction of the flow rate of the cooling flow that may be required
to cool turbine nozzle assembly 30. As discussed above, in some
known IGCC systems and/or gas turbine engines, turbine nozzle
assembly 30 is cooled using compressed air extracted from a
compressor stage of engine 10. IGCC system 110 may cool turbine
nozzle assembly 30 using carbon dioxide from clean-up device in
addition or alternative to cooling via compressor extraction air.
Accordingly, in some embodiments, conduit 112 may facilitate
increasing an overall amount of cooling of turbine nozzle assembly
30 if both carbon dioxide from clean-up device and compressor
extraction air are used to cool turbine nozzle assembly 30.
Moreover, in some embodiments, conduit 112 may facilitate
decreasing, or eliminating entirely, an amount of compressor
extraction air used to cool turbine nozzle assembly 30, which may
facilitate increasing an amount of oxygen supplied gas turbine
engine combustor 14 from gas turbine engine compressor 14.
[0026] FIG. 7 is a schematic diagram of an exemplary embodiment of
an IGCC power generation system 130 that is an alternative
embodiment of IGCC system 110 (shown in FIG. 6). In the exemplary
embodiment of IGCC system 130, a conduit 132 is coupled in flow
communication to carbon dioxide outlet 116 of clean-up device 62
that exhausts at least some of the carbon dioxide flow from device
62. Conduit 132 is also coupled in flow communication to pipe 92.
Accordingly, conduit 132 receives carbon dioxide flow exhaust from
clean-up device 62 through carbon dioxide outlet 116, and channels
the carbon dioxide flow into pipe 92, which channels the carbon
dioxide flow into the gas turbine engine cavity containing assembly
30 for directing carbon dioxide toward turbine nozzle assembly 30
to facilitate cooling assembly 30. In some embodiments, a
compressor 134 is operatively connected to conduit 132 for
compressing the carbon dioxide flow before it is supplied to gas
turbine engine 10. Moreover, in some embodiments, a valve 136 is
operatively connected at the fluid interconnection between pipe 92
and conduit 132 for selectively controlling an amount of the carbon
dioxide flow released into pipe 92. In some embodiments, conduit
132 receives all of the carbon dioxide generated by clean-up device
62 such that conduit 132 channels all of the carbon dioxide
generated by clean-up device 62 to turbine nozzle assembly 30. In
other embodiments, some of the carbon dioxide generated by clean-up
device 62 is vented to the atmosphere.
[0027] By using the carbon dioxide flow that may otherwise be
wasted by being vented to the atmosphere, IGCC system 130 may
facilitate reducing parasitic energy losses experienced by system
130. Moreover, because the carbon dioxide flow exits clean-up
device 62 at about ambient temperature and at least a substantial
portion of conduit 132 is external to gas turbine engine 10, a
temperature of the carbon dioxide flow can be heated/controlled to
any desired temperature and may thereby facilitate allowing a
reduction of the flow rate of the cooling flow that may be required
to cool turbine nozzle assembly 30. IGCC system 130 may cool
turbine nozzle assembly 30 using carbon dioxide from clean-up
device 62 in addition or alternative to cooling via compressor
extraction air. Accordingly, in some embodiments, conduit 132 may
facilitate increasing an overall amount of cooling of turbine
nozzle assembly 30 if both carbon dioxide from clean-up device 62
and compressor extraction air are used to cool turbine nozzle
assembly 30. Moreover, in some embodiments, conduit 132 may
facilitate decreasing, or eliminating entirely (despite using pipe
92 to ultimately supply carbon dioxide to assembly 30), an amount
of compressor extraction air used to cool turbine nozzle assembly
30, which may facilitate increasing an amount of oxygen supplied
gas turbine engine combustor 14 from gas turbine engine compressor
14.
[0028] Although the systems and methods described and/or
illustrated herein are described and/or illustrated with respect to
cooling a turbine nozzle assembly for a gas turbine engine,
practice of the systems and methods described and/or illustrated
herein is not limited to turbine nozzle assemblies. Rather, the
systems and methods described and/or illustrated herein are
applicable to cooling any component of a gas turbine engine turbine
assembly.
[0029] Exemplary embodiments of systems and methods are described
and/or illustrated herein in detail. The systems and methods are
not limited to the specific embodiments described herein, but
rather, components of each system, as well as steps of each method,
may be utilized independently and separately from other components
and steps described herein. Each component, and each method step,
can also be used in combination with other components and/or method
steps.
[0030] When introducing elements/components/etc. of the systems and
methods described and/or illustrated herein, the articles "a",
"an", "the" and "said" are intended to mean that there are one or
more of the element(s)/component(s)/etc. The terms "comprising",
"including" and "having" are intended to be inclusive and mean that
there may be additional element(s)/component(s)/etc. other than the
listed element(s)/component(s)/etc.
[0031] While the invention has been described in terms of various
specific embodiments, those skilled in the art will recognize that
the invention can be practiced with modification within the spirit
and scope of the claims.
* * * * *